THE OBJECTIVE OF THE PROPOSED WORK (PHASE I AND II) IS TO DEVELOP A COMPUTER PROGRAM THAT WILL AID IN THE DESIGN OF EXHAUST COOLING SYSTEMS FOR INFRARED SUPPRESSION ON AIRCRAFT. THE CODE WILL BE CAPABLE OF MODELING COMPLEX THREE-DIMENSIONAL FLOW AND HEAT TRANSFER AND WILL BE GENERAL ENOUGH SO AS TO BE USED IN A WIDE VARIETY OF PROBLEMS ASSOCIATED WITH AIRCRAFT PROPULSION, E.G., VSTOLV. THE SOFTWARE WILL BE BASED ON CREARE'S FLUID FLOW MODELING CODE FLUENT/BFC. IN PHASE I, WE WILL DEVELOP THE SPECIFICATIONS FOR THE ENHANCEMENTS TO BE ADDED TO THE PROPOSED CODE. TO DEMONSTRATE THE CURRENT CAPABILITIES OF FLUENT/BFC, WE WILL COMPUTE THE THREEDIMENSIONAL TURBULENT FLOW IN A TYPICAL VENTRAL NOZZLE CONFIGURATION. FINALLY, TO MEET THE SPECIFICATIONS, WE WILL DEVELOP A PLAN FOR THE IMPLEMENTATION OF NEW FEATURES AND CAPABILITIES THAT ARE NOT AVAILABLE IN THE BASE CODE.